I have a Disco 2 in costa rica. It has gone crazy. The M s and D lights will flash and it will go into limp home mode. I don't know what causes that to happen, it is random and is usually fixed by just stopping and restarting the car. NOW, after three hours in bumper to bumper the car started to overheat for the first time ever. I pulled over and let it cool, got abck on the road and about forty five minutes later it started to overheat again and the lights were flashing ( i never let it get fully into the red, just pulled over immediately to let it cool) When I tried to start the car, the battery was DEAD. Someone jumped me and away we went, this time it was only about twenty minutes later and as I pulled into the gas station, the car died! I waited, jumped it and went to a hotel. In the morning I drove it a hour and a half and it never died or flashed, so i assumed it was the alternator. I replaced the alternator and the battery and the problem persists. It can only go about a half hour before it overheats and lights start flashing. Where do I start to figure out what is going on. The mechanics in costa rica are not very competent about LRs unless I drive the car to san jose, which is about a four hour drive. This car will not make that drive. ( a little background that may help is that this car has never had a problem except for one small thing, the TRANSMISSION! LOL, the car has had a hard time going into reverse for a year or so, but in drive it works fine, I know we are going to have to replace the tranny, but could that have anything to do with the overheating and the M s and D lights?)

 

They are not caused by same item.
Let us deal with overheat first.
A. Coolant must be full to midpoint of reserve container. No air in system, no sound like water rushing in pipes under dash.
B. Fans working, the electric one on the air conditioner condenser, when engine hot. Big fan on radiator has a clutch, when engine is cold, spin fan by hand and release, should turn maybe 1/4 turn. When hot, same test, should not spin all the way around. If driving slow, fan must be working good.
C. Radiator should be clean inside and outside. Flush or rod out calcium build up in radiator.
D. Replace thermostat.

 

Oops you wont be able to rod out radiator. But can flush.

Check battery volts 13.8 to 14.4 at idle.

 

I am looking at the thermostats online and they are between 8 and 25 bucks. Is that the whole thing I need to replace? OEM is fine? I am going to have my husband check the fans using your advice, but when it was hot both fans seemed to be running. I will have him do those tests today.

 

I just realized something. We put a new bumper on the truck to pass RTV, the old one was damaged on the right hand side and Costa has really strict laws about those things. The old bumper had a huge space where the radiator is and air could flow in, the new one is solid and plastic, could that be preventing the right air flow into the radiator? It is from a Disco 1 i think...

 

Replace whole thermostat and go oem, it is worth the slight difference, there have been posts about aftermarket ones overheating.

When engine is hot, and off, have him spin main fan between radiator and engine block and release. Should stop quickly, not spin for a whole revolution or worse, freewheel. When engine cold this same test will feel like peanut butter inside the fan.

Radiator does need airflow to work, so if it is restricted that would impact it when going slow or stop and go traffic.

Home remedy radiator flush is add a gallon of distilled white vinegar and run for 20 minutes, then let sit over night, then flush with distilled water and refill with 50:50 coolant mix, green color. Not "Dexcool".

 

Before you start throwing parts at it, you need to first deal with the charging system, go have it tested at any local parts tore, they usally do it for free, needs to be in the 13.6 to 14.4 volt range.
As for the over heat, send me your number and I'll call and walk you thru what to do and have checked, in the mean time, quit driving it.

 

Okay, i quit driving it and it will sit until i get back there in a few months. I will reconsult this thread when i am standing by car and can do the tests.

 

Why not order this stat so you can have it installed in the near future? https://landroverforums.com/forum/di...l500110-49525/

As for M&S lights you can have electrical gremlins causing that, from weak battery to poor connections to mud inside the XYZ switch on side of transmission.